Production of organic compounds containing nitrogen



Planar! Aug. 7, 1945 J'BODUCTION OF ORGANIC CONTAINING NITROG COMPOUNDS Frank A. Apgar and John W. Teter, Chicago, 111., assignors to Sinclair Refining Company, New York, N. Y., a corporation of Maine No Drawing. Application November 5, 1942,

. Serial No.

a Claims. (01. zoo-404) This invention deals with the production of amines. nitriles and their derivatives from unsaturated hydrocarbons available in gas mixtures produced in the of hydrocarbon oilsasinthe refiningofpetroleumbydirectcatalytic reaction with ammonia. This application is in part a continuation of our application 8erial No. 289,186 filed August 9, 1939.

Organic nitrogen compounds of this sort have a variety of present uses in industry and have potentialities of wider use both as addition agents in lubricants and fuels and as raw materials for the production of other chemicals. Amines and their derivatives are useful as anti-knock agents and color stabilizers in motor fuels, as antieorrosion agents and as anti-sludging, anti-lacquering and color stabilising agents in lubricants. Nitriles are useful oiliness agents in lubricants and are easily converted to amines. The cost of production by present commercial methods is considerable and restricts the use of these chemicals. Some of the higher molecular weight compounds, for instance the aliphatic amines of more than four or five carbon atoms, are not produced commercially but are useful as lubricant addition agents.

The object of this invention is to produce such compounds, of low or high molecular weight, in

an economical way.

Generically, the reaction of direct amination is one in which one N-H bond is activated and in which the oleflne double bond is in the active The secondary amineis formed by substitution for one of the hydrogen atoms of the amino radical in the primary amine, involving activation of another N-H bond. Similarly for-the tertiary amine in relation to the secondary amine.

To obtain yields of commercial significance,

it is essential to employ a selective catalyst which effectively promotes the direct amination reaction in competition with polymerization of the oieiineandwithotherreactlonssuchsshydrogenation. crackirk or dehy drogenation. A number of catalysts have been found which, with different degrees of eifectiveness, activate an I N-H bond of ammonia and the oleflne double bond and thereby promote the amination reaction. Among these are iron. nickel and cobalt. While the reaction takes place to some extent at atmospheric pressure, better yields are obtained at higher pressures. Temperatures ran in from about 400 F. to about 725 F. are useful. The optimum temperature varies with the particular oleiine and with the activity of the catalyst. Thus with an unpromoted cobalt catalyst suspended on washed asbestos fibers the optimum temperature as applied to a high molecular weight oleilne such as n-dodecene-l approximates 500 F.-550 FL, while as applied to propylene, the optimum temperature approximates 675 l t-700 F. In general as applied to oleiines containing more than 3 carbon atoms. temperatures ranging from about 400 F. to about 650 F. are useful.

An example of the invention as applied to high molecular weight compounds is as follows: An oleflne, n-dodecene-l, is reacted with anhydrous ammonia, in a 1 to 1.64 molar ratio, in the presence of an active unpromoted cobalt catalyst suspended on washed asbestos fibers. A temperature of 500 F. to 550 F. is maintained for 20 hours. If carried out in a closed system, as

state. The reaction proceeds when the reactants,

in a bomb. a pressure of 2000 pounds per square inch is developed. There is a drop of about 120 pounds per square inch as the reaction proceeds. At the end of the run, unreacted ammonia is removed by stabilization and unreacted oleiine is distilled off, leaving theoleflne-free product which may be mixed with the product extracted from the catalyst mass, after removal of the benzene used as the extractant.

About to of the oleilne is consumed under the conditions stated. The organic nitrogen compounds produced equal about 12% by weight of the oleflne charged or 20% to 25% of the oleiine consumed; and consist of primary lauryl amine, di-lauryl amine, lauro-nitrile and,

under some conditions, lauric acid amide. These are recovered in fractions by distillation of the reaction product. Unreacted oleilne and ammonia are recycled. when precautions are taken to avoid the presence of. adventitious oxygen, including oxygen in the form of water, the lauric acid amide is not produced in appreciable amount. Oxygen or oxygen compounds are not necessary to the nitrogen fixation. In addition. there is some formation of useful low boiling nitrogen compounds of fewer carbon atoms than the olenne charged, e. g., octo-nitrile. Other side reactions yield parailins by hydrogenation or new olefins by polymerisation.

A typical yield under the conditions stated is:

The product identified above as organic nitrogen, forming 22.6% of the olefine consumed, consists on the same basis of about 1% of octo-nitrile, about of primary lauryl amine and lauronitrile, with a slight amount of polymer olefine, and about 1.5% of di-lauryl amine.

The catalyst in the example given is prepared by suspending washed asbestos fibers in an aqueous solution of cobalt acetate to which aqueous sodium hydroxide is added slowly with good agitation, following which the mass is filtered, washed with distilled water and then gradually increased in temperature to 650 F. Th cobalt is then reduced to an active catalytic metal by exposure to a slow stream of hydrogen for about 100 hours at 550 F. The final catalyst mass contains about 27% of cobalt by weight. In reacting 6.8 mols of n-dodecene-l in a three liter shaker bomb, a catalyst mass of 300 grams is used. After the run, the mass is freed of reaction products by benzene extraction, which permits recovery of such products by subsequent removal of the benzene.

Reduced FeaO promoted with 1.59% K20 and 1.31% A1203 is a useful catalyst, best results being obtained when the time of reduction is relatively short and the temperature relatively high. For example, reduction at 850 1'. for 32 hours gives a better catalyst than reduction for 6 hours at 750 F. or for much longer times at 850 F.

Other olefines than dodecene may be used with corresponding diiference in the number of carbon atoms in the product. For example, amines are produced by catalytic reaction of ammonia with the heptene and octene fractions of polymer gasoline boiling between 175 and 250 F., or with hydrocarbon mixtures including gas olefines such as are found in stabilizer reflux. Frequently there also is formation of useful organic nitrogen com- Reduced NiaOa gives better results than the iron catalyst. Increased length of the period of reduction shows no great improving eii'ect. Equally satisfactory catalysts, within insignificant limits, may be prepared at 16 hours and 100 hours. Reduction at 540-550 F., for 100 hours, is somewhat better than reduction at 510 F. for 16 hours. Reduction of Ni(0H): for 24. hours at w 575 F. produces a catalyst which, supported on asbestos fibers, gives an amine yield of about 5% of the olefine charge, or close to half the yield obtained with reduced cobalt similarly supported.

All of the following metallic catalysts promote. to some extent the direct amination of oleflnes with ammonia. By a "metallic" catalyst, as used herein and in the claims, is meant free metals. metallic oxides and metallic salts.

Promoter Support K30 and shot...

Asbestos fibers.

. MgO.

Asbestos ilbers. Do.

. Do. M101.

( i P xm'n'oso.

pounds containing a greater number of carbon atoms than the olefin charged.

This process of direct amination of oleilnes using a selected catalyst affords a new and less expensive wa of producing amines, nitriles and their derivatives, and of producing certain amines, nitriles and derivatives which have not hitherto been produced by commercial methods.

We claim:

1. In the production of amines and nitriles, the improvement which comprises reacting an oleflne containing more than three carbon atoms with ammonia at a temperature of about 400 F. to about 650 F. in the presence of a metallic catalyst selectively promoting the amination reaction.

2. In the production of amines and nitriles. the improvement which comprises reacting an oleflne containing more than three carbon atoms with ammonia at a temperature of about 400 1". to about 650' I". in the presence of a metallic catalyst selectively activating the N-H bond and the oleilne double bond.

3. In the production of amines and nitriles, the improvement which comprises reacting an oleilne containing more than four carbon atoms with ammonia at a temperature of about 400 1". to about 650 F. in the presence of a metallic catalyst selectively promoting the amination reaction.

4. In the production of amines and nitriles, the improvement which comprises reacting an oleiine with ammonia at a temperature of about 400 F. to about 725 1". in the presence of a cobalt catalyst.

5. In the production of amines and nitriles, the improvement which comprises reacting a hydrocarbon gas mixture including oleflnes containing more than three carbon atoms with ammonia at a temperature of about 400 F. to about 650 F. in the presence of a metallic catalyst selectively promoting the amination reaction.

6. In the production of amines and nitriles, the improvement which comprises reacting .a dodecene with ammonia at a temperature of about 400 F. to about 650 F. in the presence of a metallic catalyst selectively promoting the amino.- tion reaction.

7. In the production of amines and nitriles, the improvement which comprises reacting an oleilne containing more than three carbon atoms with ammonia at a temperature of about 400 F. to about 650' F. in the presence of a catalyst of the group consisting of iron, nickel and cobalt.

8. In the production of amines and nitriles. the improvement which comprises reacting an oleflne with ammonia at a temperature of about 400 F. to about 725' F. in the presence of a catalyst comprising metallic cobalt suspended on asbestos fibers.

FRANK A. APGAR. JOHN W. TETER. 

